Yellow Wiggle Emma Watkins has revealed she's stepping away from the group's Australian tour, due to a serious health issue.

The 28-year-old has been diagnosed with endometriosis and requires surgery.

She told TODAY's Georgie Gardner the decision to take a break from The Wiggles was difficult.

"I think even for me it was a really big shock," she says.

"Over the last couple of years I'd noticed a lot of pain and I think, even as a girl, you're used to dealing with what you have to deal with.

(Instagram/emma_wiggle)

"As it started to progress, to get a little bit worse, I thought 'I should get it checked out'.

"I think I've almost left it too long and I realised that lots of people don't even think about going to see somebody earlier."

Endometriosis is a condition in which tissue that normally lines the uterus grows outside of it, according to Endometriosis Australia.

The extra tissue can be found on the ovaries, fallopian tubes or the intestines.

It can be painful and may cause infertility.

Emma, who is the first female Wiggle, says she experienced pain while performing with the popular children's band.

(Instagram/emma_wiggle)

"I just thought it was a really bad period and really heavy bleeding and I really didn't think much of it.

"I got headaches through the show and I thought, 'OK this is probably a little too much now'."

Emma says she has "quite a few" cysts and admits the surgery will be difficult.

"I need to take the rest quite soon and I need to be serious about looking at my health as a priority."

The performer, who married Purple Wiggle Lachlan Gillespie in April 2016, says she needs the surgery to help increase her chances of falling pregnant.

Emma and husband Lachlan married in April 2016. (Instagram/emma_wiggle)

She's now urging other women to seek help if they are in pain.

"It's so common at the moment – it's one in 10 women in Australia – that suffer from endometriosis but may be seven or 10 years delayed in diagnosis.

"So if I can spread awareness about checking up on your symptoms, and if you do have pain go and see somebody because I know it has been the best thing for me."

Emma will take a break from performing throughout April and May, with an understudy to wear her Yellow Wiggle skivvy.

"A friend of mine is going to be dressing up as Emma and will be singing all the Emma songs and dances so everyone will still be there – Anthony, Lachy, Simon – and of course Dorothy the Dinosaur, Wags the Dog, Henry [the Octopus] and Captain Feathersword."